Journal of Computer Science and Technology

, Volume 3, Issue 2, pp 131–138 | Cite as

Data dependencies in database with incomplete information

  • Zhang Yan 
  • He Jichao 
Regular Papers


To get more meaning of incomplete information, a predicate way is proposed to represent the nulls. The concepts of functional and multivalued dependencies are extended in the environment which allows nulls in a database relation. The inference rules which can be applied to the extended dependencies are investigated. Finally it is shown that the rules are complete for the family of extended functional and multivalued dependencies.


Relational Database Incomplete Information Functional Dependency Inference Rule Data Dependency 


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Copyright information

© Science Press, Beijing China and Allerton Press Inc. 1988

Authors and Affiliations

  • Zhang Yan 
    • 1
  • He Jichao 
    • 2
  1. 1.Wuhan UniversityWuhanChina
  2. 2.Nanjing Institute of TechnologyNanjingChina

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